do not add stray newlines

Author: cscheid

src/core/handlers/base.ts

@@ -405,9 +405,7 @@ export async function expandIncludes(
   const newCells: MappedString[] = [];
   for (let i = 0; i < mdCells.length; ++i) {
     const cell = mdCells[i];
-    newCells.push(
-      i === 0 ? cell.sourceVerbatim : mappedConcat(["\n", cell.sourceVerbatim]),
-    );
+    newCells.push(cell.sourceVerbatim);
   }
 
   await processMarkdownIncludes(newCells, options, filename);
@@ -437,9 +435,7 @@ export async function handleLanguageCells(
 
   for (let i = 0; i < mdCells.length; ++i) {
     const cell = mdCells[i];
-    newCells.push(
-      i === 0 ? cell.sourceVerbatim : mappedConcat(["\n", cell.sourceVerbatim]),
-    );
+    newCells.push(cell.sourceVerbatim);
     if (
       cell.cell_type === "raw" ||
       cell.cell_type === "markdown"
@@ -483,7 +479,6 @@ export async function handleLanguageCells(
           (innerLanguageHandler.stage !== "any" &&
             innerLanguageHandler.stage !== options.stage)
         ) { // we're in the wrong stage, so we don't actually do anything
-          newCells[cell.index] = mappedConcat([newCells[cell.index], "\n"]);
           continue;
         }
         if (
@@ -492,7 +487,6 @@ export async function handleLanguageCells(
         ) {
           // if no handler is present (or a directive was included for something
           // that responds to cells instead), we're a no-op
-          newCells[cell.index] = mappedConcat([newCells[cell.index], "\n"]);
           continue;
         }
         if (innerLanguageHandler.directive === undefined) {